Currency cassettes provide ATMs with a source of banknotes, and are strong metal or plastics boxes comprising a lid releasably coupled to a body. One end of the body includes a covered aperture that is automatically opened when the cassette is inserted into a currency dispenser, and automatically closed when the cassette is removed from the currency dispenser. The opposite end of the body includes a handle for carrying the cassette, and to aid insertion and removal of the cassette. When a cassette is inserted into a currency dispenser, only the handle end of the cassette is visible.
Vacuum picking systems are used in some automated teller machines to pick banknotes or other media from such cassettes. Vacuum systems include some form of pump mechanism for sucking air through a tube, which has a suction cup on its end. The suction cup is located on the end of a movable pick arm. In use, the arm and associated suction cup is moved into contact with a banknote, at the front of a stack of notes in the cassette, so that the suction created by the pump causes the banknote to adhere to the cup.
Also associated with each arm is gearing or other mechanical means for moving the end of the arm into contact with the banknote, and then towards a transport means which feeds the notes to a dispensing location from which a user can collect the dispensed banknotes. This gearing is normally powered by an AC motor.
There is a known problem with pick mechanisms (such as vacuum pick and friction pick mechanisms), known as double picking, when more than one note at a time is picked from the note stack. This problem is caused, in particular, by worn or poor quality notes. In addition, the use of polymer notes exacerbates this problem.
Double picking of notes causes detrimental performance in ATM cash dispensers and results in overfilling of purge bins, to which double picked notes are diverted, requiring intervention by an ATM engineer.
More recently there has become an increasing need to reduce the amount of space taken up by the media cassette itself within an ATM or self-service terminal (SST) as a whole. This is because of space restrictions at locations where ATMs and SSTs are provided. In addition, when media cassettes are in transit or storage before being inserted into ATMs or SSTs there is also a need to conserve space.
Other problems relate to the filling of the media cassettes themselves for example, to load bank notes into the media cassette. If the media cassette is overfilled this can cause problems with picking of media from the cassette because double-picking is more likely to occur for example. ATM operatives are often tempted to overfill the media cassettes thinking that this will save time and replenishment costs, whilst in reality it often leads to more problems and increased service costs.
As mentioned above, media cassettes are often transported and moved about before being inserted into a pick unit within a dispenser of an ATM or SST. For example, they are loaded in and out of vehicles during transit from a bank to an ATM or SST location. During such transit there is a need to secure stacked media within the cassette to prevent this stack from moving and becoming disarrayed. Previously this has been achieved by using a pusher plate to urge the stack of media items to one end of the cassette and to lock this pusher plate into position during transit of the whole cassette.
There is also a need to retain some small degree of flexibility and movement in the media stack when the cassette is installed in the ATM or SST and is in use.
During this time, it is important to have some flexibility and movement in the media stack to reduce the likelihood of double-picking and other problems with the picking mechanism. Previously, this has been achieved by releasing the pusher plate when the cassette is installed in an ATM, SST or the like.
During transportation of media cassettes there is also a risk that the media cassette will be dropped on its end or body. This can cause problems with the pusher plate locking mechanism, causing it to unlock and possibly become damaged.
The invention seeks to provide an improved media cassette pusher plate locking mechanism which addresses or at least mitigates one or more of the problems mentioned above.